In
amplitude modulation (AM), a
band of frequencies higher than or lower than the
carrier frequency , containing energy as a result of the modulation process. (
188 )
Note: Amplitude modulation results in two sidebands. The frequencies above the carrier frequency constitute what is referred to as the
"upper sideband" those below the carrier frequency, constitute the
"lower sideband." In conventional AM
transmission , both sidebands are present. Transmission in which one sideband is removed is called
"single-sideband transmission ."